Methods of preparing new taxoids and pharmaceutical compositions containing them

ABSTRACT

Methods of preparing new taxoids of general formula (I) are presented:                    
     in which: 
     R 4  represents an alkanoyloxy radical in which the alkanoyl portion contains 2 to 6 carbon atoms in an unbranched or branched chain, this radical unsubstituted or substituted with one or more halogen atoms, an alkoxy radical containing 1 to 4 carbon atoms, or alternatively R 4  represents a cycloalkanoyloxy radical in which the cycloalkanoyl portion contains 4 to 8 carbon atoms, or alternatively R 4  represents a benzoyloxy radical; 
     R 5  represents an alkoxy radical containing 1 to 4 carbon atoms, substituted by an alkylthio radical containing 1 to 4 carbon atoms; and 
     Z represents a hydrogen atom or a radical of general formula:

This is a continuation-in-part of U.S. patent application Ser. No.09/271,300, filed Mar. 17, 1999, now U.S. Pat. No. 6,040,466, which is acontinuation-in-part of U.S. patent application Ser. No. 08/913,972,filed on Sep. 26, 1997, now U.S. Pat. No. 5,889,043; and a continuationof PCT/FR96/00441, filed Mar. 25, 1996, all of which are incorporatedherein by reference.

The present invention relates to methods of preparing new taxoids ofgeneral formula:

in which:

Z represents a hydrogen atom or a radical of general formula:

in which:

R₁ represents a benzoyl radical optionally substituted with one or moreidentical or different atoms or radicals chosen from halogen atoms andalkyl radicals containing 1 to 4 carbon atoms, alkoxy radicalscontaining 1 to 4 carbon atoms or trifluoromethyl radicals, a thenoyl orfuroyl radical or a radical R₂—O—C(═O)— in which

R₂ represents:

an alkyl radical containing 1 to 8 carbon atoms, an alkenyl radicalcontaining 2 to 8 carbon atoms, an alkynyl radical containing 3 to 8carbon atoms, a cycloalkyl radical containing 3 to 6 carbon atoms, acycloalkenyl radical containing 4 to 6 carbon atoms, a phenyl radical(unsubstituted or substituted with one or more atoms or radicalsselected from halogen atoms, alkyl radicals containing 1 to 4 carbonatoms, and alkoxy radicals containing 1 to 4 carbon atoms), cyanoradicals, carboxyl radicals, and alkoxycarbonyl radicals in which thealkyl portion contains 1 to 4 carbon atoms;

a phenyl or an α- or β-naphthyl radical radical, which is unsubstitutedor substituted with one or more atoms or radicals selected from halogenatoms, alkyl radicals containing 1 to 4 carbon atoms, alkoxy radicalscontaining 1 to 4 carbon atoms, and a 5-membered aromatic heterocyclicradical;

R₃ represents a phenyl radical;

R₄ represents an alkanoyloxy radical in which the alkanoyl portioncontains 2 to 6 carbon atoms in an unbranched or branched chain, thisradical being unsubstituted or substituted with one or more halogenatoms or with an alkoxy radical containing 1 to 4 carbon atoms, oralternatively R₄ represents a cycloalkanoyloxy radical in which thecycloalkanoyl portion contains 4 to 8 carbon atoms, or alternatively R₄represents a benzoyloxy radical; and

R₅ represents an alkoxy radical containing 1 to 4 carbon atoms in anunbranched or branched chain, substituted by an alkylthio radicalcontaining 1 to 4 carbon atoms.

Preferably, the radical R₄ represents an alkanoyloxy radical in whichthe alkanoyl portion contains 2 to 6 carbon atoms, or a cycloalkanoyloxyradical in which the cycloalkanoyl portion contains 4 to 8 carbon atoms.

More especially, the present invention relates to the products ofgeneral formula (I) in which Z represents a hydrogen atom or a radicalof general formula (II) in which

R₁ represents a benzoyl radical, or a radical R₂—O—C(═O)—, in which

R₂ represents a tert-butyl radical, and

R₃ represents a phenyl radical, and

R₄ represents an alkanoyloxy radical in which the alkanoyl portioncontains 2 to 4 carbon atoms, and

R₅ represents an alkoxy group containing 1 to 4 carbon atoms substitutedby a methylthio radical.

Still more especially, the present invention relates to the products ofgeneral formula (I) in which Z represents a hydrogen atom or a radicalof general formula (II) in which R₁ represents a benzoyl radical or aradical R₂O—C(═O)— in which R₂ represents a tert-butyl radical and R₃represents a phenyl radical, R₄ represents an acetoxy, or amethoxyacetoxy radical, and R₅ represents a methylthiomethoxy radical.

The products of general formula (I) in which Z represents a radical ofgeneral formula (II) display noteworthy anti-tumor and anti-leukemicproperties.

According to the present invention, the new products of general formula(I) in which Z represents a radical of general formula (II) may beobtained by esterification of a product of general formula:

in which R₄ and R₅ are defined as above, by means of an acid of generalformula:

in which R₁ and R₃ are defined as above, and either R₆ represents ahydrogen atom and R₇ represents a group protecting the hydroxylfunction, or R₆ and R₇ together form a saturated 5- or 6-memberedheterocycle, or by means of a derivative of this acid, to obtain anester of general formula:

in which R₁, R₃, R₄, R₅, R₆ and R₇ are defined as above, followed byreplacement of the protective groups represented by R₇ and/or R₆ and R₇by hydrogen atoms.

The esterification by means of a product of general formula (XII):

R′₄—X₁   (XII)

in which R′₄ is such that R′₄—O— is identical to R₄ defined as above butcannot represent a hydrogen atom or a hydroxyl radical, and in which X₁represents a hydroxyl radical, may be performed in the presence of acondensing agent (carbodiimide, reactive carbonate) and an activatingagent (aminopyridines) in an organic solvent (ether, ester, ketones,nitrites, aliphatic hydrocarbons, halogenated aliphatic hydrocarbons,aromatic hydrocarbons) at a temperature of between −10 and 90° C.

The esterification may also be carried out using a product of generalformula (XII) in which X₁ represents a radical R₄—O—, working in thepresence of an activating agent (aminopyridines) in an organic solvent(ethers, esters, ketones, nitriles, aliphatic hydrocarbons, halogenatedaliphatic hydrocarbons, aromatic hydrocarbons) at a temperature ofbetween 0 and 90° C.

The esterification may also be carried out using a product of generalformula (XII) in which X₁ represents a halogen atom, in the presence ofa base (tertiary aliphatic amine), working in an organic solvent(ethers, esters, ketones, nitriles, aliphatic hydrocarbons, halogenatedaliphatic hydrocarbons, aromatic hydrocarbons) at a temperature ofbetween 0 and 80° C.

Preferably, R₆ represents a hydrogen atom and R₇ represents a groupprotecting the hydroxyl function, or alternatively R₆ and R₇ togetherform a saturated 5- or 6-membered heterocycle.

When R₆ represents a hydrogen atom, R₇ preferably represents amethoxymethyl, 1-ethoxyethyl, benzyloxymethyl, trimethylsilyl,triethylsilyl, β-trimethylsilylethoxymethyl, benzyloxycarbonyl ortetrahydropyranyl radical.

When R₆ and R₇ together form a heterocycle, the latter is preferably anoxazolidine ring optionally monosubstituted or gem-disubstituted atposition 2.

Replacement of the protective groups R₇ and/or R₆ and R₇ by hydrogenatoms may be performed, depending on their nature, in the followingmanner:

1) when R₆ represents a hydrogen atom and R₇ represents a groupprotecting the hydroxyl function, replacement of the protective groupsby hydrogen atoms is performed by means of an inorganic acid(hydrochloric acid, sulfuric acid, hydrofluoric acid) or organic acid(acetic acid, methanesulfonic acid, trifluoromethanesulfonic acid,p-toluenesulfonic acid) used alone or mixed, working in an organicsolvent chosen from alcohols, ethers, esters, aliphatic hydrocarbons,halogenated aliphatic hydrocarbons, aromatic hydrocarbons or nitrites ata temperature of between −10 and 60° C.,

2) when R₆ and R₇ together form a saturated 5- or 6-memberedheterocycle, and more especially an oxazolidine ring of general formula:

in which R₁ is defined as above and R₈ and R₉, which may be identical ordifferent, represent a hydrogen atom or an alkyl radical containing 1 to4 carbon atoms, or an arylalkyl radical in which the alkyl portioncontains 1 to 4 carbon atoms and the aryl portion preferably representsa phenyl radical optionally substituted with one or more alkoxy radicalscontaining 1 to 4 carbon atoms, or an aryl radical preferablyrepresenting a phenyl radical optionally substituted with one or morealkoxy radicals containing 1 to 4 carbon atoms, or alternatively R₈represents an alkoxy radical containing 1 to 4 carbon atoms or atrihalomethyl radical such as trichloromethyl or a phenyl radicalsubstituted with a trihalomethyl radical such as trichloromethyl and R₉represents a hydrogen atom, or alternatively R₈ and R₉, together withthe carbon atom to which they are linked, form a 4- to 7-membered ring,replacement of the protective group formed by R₆ and R₇ by hydrogenatoms may be performed, depending on the meanings of R₁, R₈ and R₉, inthe following manner:

a) when R₁ represents a tert-butoxycarbonyl radical and R₈ and R₉, whichmay be identical or different, represent an alkyl radical or anarylalkyl (benzyl) or aryl (phenyl) radical, or alternatively R₈represents a trihalomethyl radical or a phenyl radical substituted witha trihalomethyl radical and R₉ represents a hydrogen atom, oralternatively R₈ and R₉ together form a 4- to 7-membered ring, treatmentof the ester of general formula (V) with an inorganic or organic acid,where appropriate in an organic solvent such as an alcohol, yields theproduct of general formula:

in which R₃, R₄ and R₅ are defined as above, which is acylated by meansof benzoyl chloride in which the phenyl ring is optionally substitutedor by means of thenoyl chloride, of furoyl chloride or of a product ofgeneral formula:

R₂—O—C(═O)—X   (VIII)

in which R₂ is defined as above and X represents a halogen atom(fluorine, chlorine) or a residue —O—R₂ or —O—C(═)—O—R₂, to obtain aproduct of general formula (I) in which Z represents a radical ofgeneral formula (II).

Preferably, the product of general formula (V) is treated with formicacid at a temperature in the region of 20° C. to yield the product ofgeneral formula (VII).

Preferably, the acylation of the product of general formula (VII) bymeans of a benzoyl chloride in which the phenyl radical is optionallysubstituted or by means of thenoyl chloride, of furoyl chloride or of aproduct of general formula (VIII) is performed in an inert organicsolvent chosen from esters such as ethyl acetate, isopropyl acetate orn-butyl acetate and halogenated aliphatic hydrocarbons such asdichloromethane or 1,2-dichloroethane, in the presence of an inorganicbase such as sodium bicarbonate or an organic base such astriethylamine. The reaction is performed at a temperature of between 0and 50° C., and preferably in the region of 20° C.

b) when R₁ represents an optionally substituted benzoyl radical, athenoyl or furoyl radical or a radical R₂O—C(═O)— in which R₂ is definedas above, R₈ represents a hydrogen atom or an alkoxy radical containing1 to 4 carbon atoms or a phenyl radical substituted with one or morealkoxy radicals containing 1 to 4 carbon atoms and R₉ represents ahydrogen atom, replacement of the protective group formed by R₆ and R₇by hydrogen atoms is performed in the presence of an inorganic acid(hydrochloric acid, sulfuric acid) or organic acid (acetic acid,methanesulfonic acid, trifluoromethane-sulfonic acid, p-toluenesulfonicacid) used alone or mixed in a stoichiometric or catalytic amount,working in an organic solvent chosen from alcohols, ethers, esters,aliphatic hydrocarbons, halogenated aliphatic hydrocarbons and aromatichydrocarbons at a temperature of between −10 and 60° C., and preferablybetween 15 and 30° C.

According to the invention, the products of general formula (III), thatis to say the products of general formula (I) in which Z represents ahydrogen atom and R₄ and R₅ are defined as above, may be obtained from10-deacetylbaccatin III of formula:

It can be especially advantageous to protect the hydroxyl functions atthe positions 7 and 13 selectively, for example in the form of a silyldiether which may be obtained by the action of a silyl halide of generalformula:

(R)₃—Si—Hal   (X)

in which the symbols R, which may be identical or different, representan alkyl radical containing 1 to 4 carbon atoms, optionally substitutedwith a phenyl radical, or a phenyl radical, on 10-deacetylbaccatin III,to obtain a product of general formula:

in which R is defined as above, followed by the action of a product ofgeneral formula:

R′₄—X₁   (XII)

R′₄ is such that R′₄—O— is identical to R₄ defined as above but cannotrepresent a hydrogen atom or a hydroxyl radical, and X₁ represents ahalogen atom, to obtain a product of general formula:

in which R and R₄ are defined as above, the silyl protective groups ofwhich are replaced by hydrogen atoms to obtain a product of generalformula:

in which R₄ is defined as above, which is etherified selectively atposition 7 by the action of a product of general formula:

R′₅—X₂   (XV)

in which R′₅ is such that R′₅—O— is identical to R₅ defined as above andX₂ represents a halogen atom or a sulfuric or sulfonic ester residue, togive the product of general formula (III).

Generally, the action of a silyl derivative of general formula (X) on10-deacetylbaccatin III is performed in pyridine or triethylamine, whereappropriate in the presence of an organic solvent such as an aromatichydrocarbon, for instance benzene, toluene or xylenes, at a temperaturebetween 0° C. and the refluxing temperature of the reaction mixture.

Generally, the action of a product of general formula (XII) on a productof general formula (XI) is performed, after metalation of the hydroxylfunction at position 10 by means of an alkali metal hydride such assodium hydride, an alkali metal amide such as lithium amide or an alkalimetal alkylide such as butyllithium, working in an organic solvent suchas dimethylformamide or tetrahydrofuran at a temperature of between 0and 50° C.

Generally, the replacement of the silyl protective groups of the productof general formula (XIII) by hydrogen atoms is performed by means of anacid such as hydrofluoric acid or trifluoroacetic acid in the presenceof a base such as triethylamine or pyridine optionally substituted withone or more alkyl radicals containing 1 to 4 carbon atoms, the baseoptionally being combined with an inert organic solvent such as anitrile, for instance acetonitrile, or a halogenated aliphatichydrocarbon such as dichloromethane at a temperature of between 0 and80° C.

Generally, the action of a product of general formula (XV) on a productof general formula (XIV) is performed under the conditions describedabove for the action of a product of general formula (XII) on a productof general formula (XI).

According to the invention, the products of general formula (I) in whichZ represents a radical of general formula (II), and R₄ and R₅ aredefined as above may be obtained from a product of general formula:

in which R₁, R₃, R₆ and R₇ are defined as above, by silylation atposition 7 by means of a product of general formula (X), to obtain aproduct of general formula:

in which R, R₁, R₃, R₆ and R₇ are defined as above, which isfunctionalized at position 10 by means of a product of general formula(XII) to give a product of general formula:

in which R, R₁, R₃, R₄, R₆ and R₇ are defined as above, the silylprotective group of which is replaced by a hydrogen atom to give aproduct of general formula:

which, by the action of a product of general formula (XV), yields theproduct of general formula (V), the protective groups of which arereplaced by hydrogen atoms to give a product of general formula (I) inwhich Z represents a radical of general formula (II).

The reactions used for silylation, functionalization and replacement ofthe protective groups by hydrogen atoms are performed under conditionssimilar to those described above.

The products of general formula (XVI) may be obtained under theconditions described in European Patent EP 0 336 841 and InternationalApplications PCT WO 92/09589 and WO 94/07878, or from the products ofgeneral formula:

in which R₁ and R₃ are defined as above, according to known methods forprotecting the hydroxyl function of the side chain without affecting theremainder of the molecule.

According to the invention, the products of general formula (1) in whichZ represents a hydrogen atom or a radical of general formula (II) may beobtained by the action of activated Raney nickel, in the presence of analiphatic alcohol containing 1 to 3 carbon atoms, on a product ofgeneral formula:

in which R₄ is defined as above and R′ and R″, which may be identical ordifferent, represent a hydrogen atom or an alkyl radical containing 1 to6 carbon atoms, an alkenyl radical containing 2 to 6 carbon atoms, analkynyl radical containing 2 to 6 carbon atoms, a cycloalkyl radicalcontaining 3 to 6 carbon atoms or a cycloalkenyl radical containing 3 to6 carbon atoms, or alternatively R′ and R″, together with the carbonatom to which they are linked, form a cycloakyl radical containing 3 to6 carbon atoms or a cycloalkenyl radical containing 4 to 6 carbon atoms,and Z, represents a hydrogen atom or a radical of general formula:

in which R₁ and R₃ are defined as above, and either R₆ represents ahydrogen atom and R₇ represents a group protecting the hydroxylfunction, or R₆ and R₇ together form a saturated 5- or 6-memberedheterocycle, and R₄ is defined as above, to obtain a product of generalformula:

in which R₁, R₃, R₄, R₅, R₆, and R₇ are defined as above, followed, whenZ₁ represents a radical of general formula (XXII), that is to say whenthe product of general formula (XXIII) is identical to the product ofgeneral formula (V), by replacement of the protective groups representedby R₆ and/or R₆ and R₇ by hydrogen atoms under the conditions describedabove.

Generally, the action of activated Raney nickel in the presence of thealiphatic alcohol is performed at a temperature of between −10 and 60°C.

According to the invention, the product of general formula (XXI) inwhich Z₁ and R₄ are defined as above may be obtained by the action of adialkyl sulfoxide of general formula:

in which R′ and R″ are defined as above, on a product of general formula(XIX).

Generally, the reaction of the sulfoxide of general formula (XXIV),preferably dimethyl sulfoxide, with the product of general formula (XIX)is performed in the presence of a mixture of acetic acid and aceticanhydride or a derivative of acetic acid such as a haloacetic acid at atemperature of between 0 and 50° C., and preferably in the region of 25°C.

According to the invention, the products of general formula (I) in whichZ represents a radical of general formula (II) may be obtained by theaction of a product of general formula (XII) on a product of generalformula:

in which R₁, R₃, R₅, R₆ and R₇ are defined as above, working under theconditions described for the action of a product of general formula(XII) on a product of general formula (XI), followed by replacement ofthe protective groups represented by R₇, or R₆ and R₇, by hydrogen atomsunder the conditions described above.

The product of general formula (XXV) may be obtained by the action of azinc halide such as zinc iodide or hydrazine on a product of generalformula:

in which R₁, R₃, R₅, R₆, and R₇ are defined as above.

Generally, the reaction is performed working in an aliphatic alcoholcontaining 1 to 4 carbon atoms, such as methanol or ethanol, at atemperature of between 0 and 50° C.

The product of general formula (XXVI) may be obtained by the action ofactivated Raney nickel in the presence of an aliphatic alcoholcontaining 1 to 3 carbon atoms on a product of general formula:

in which R₁, R₃, R₆, R₇, R′ and R″ are defined as above, working underthe conditions described above for the preparation of a product ofgeneral formula (I) from a product of general formula (XXI).

The product of general formula (XXVII) may be obtained by the action ofa sulfoxide of general formula (XXIV) on a product of general formula:

in which R₁, R₃, R₆ and R₇ are defined as above, working under theconditions described above for the action of a sulfoxide of generalformula (XXIV) on a product of general formula (XIX).

The product of general formula (XXVIII) may be obtained from a productof general formula:

in which R₁, R₃, R₆ and R₇ are defined as above, working under theconditions described above for replacing the silyl groups of the productof general formula (XIII) by hydrogen atoms.

The product of general formula (XXIX) may be prepared under theconditions described in International Application PCT WO 95/11241.

The new products of general formula (I) obtained by carrying out theprocesses according to the invention may be purified according to knownmethods such as crystallization or chromatography.

The products of general formula (I) in which Z represents a radical ofgeneral formula (II) display noteworthy biological properties.

In vitro measurement of the biological activity was performed on tubulinextracted from pig's brain by the method of M. L. Shelanski et al.,Proc. Natl. Acad. Sci. USA, 70, 765-768 (1973). Study of thedepolymerization of microtubules to tubulin was performed according tothe method of G. Chauviere et al., C. R. Acad. Sci., 293, series II,501-503 (1981). In this study, the products of general formula (I) inwhich Z represents a radical of general formula (II) were shown to be atleast as active as TAXOL® (paclitaxel) and TAXOTERE® (docetaxel).

In vivo, the products of general formula (I) in which Z represents aradical of general formula (II) were shown to be active in mice graftedwith B16 melanoma at doses of between 1 and 10 mg/kg administeredintraperitoneally, as well as on other liquid or solid tumors.

The new products have anti-tumor properties, and more especiallyactivity against tumors which are resistant to TAXOL® (paclitaxel) or toTAXOTERE® (docetaxel). Such tumors comprise colon tumors which have ahigh expression of the mdr1 gene (multiple drug resistance gene).Multiple drug resistance is a customary term relating to the resistanceof a tumor to different products having different structures andmechanisms of action. Taxoids are generally known to be stronglyrecognized by experimental tumors such as P388/DOX, a cell line selectedfor its resistance to doxorubicin (DOX) which expresses mdr1.

The examples which follow illustrate the present invention.

EXAMPLE 1

243 mg of4α-acetoxy-2α-benzoyloxy-5β,20-epoxy-1β-hydroxy-7β-methoxy-9-oxo-10β-(3-pyridylcarbonyl)oxy-11-taxen-13α-yl(2R,4S,5R)-3-tert-butoxycarbonyl-2-(4-methoxyphenyl)-4-phenyl-1,3-oxazolidine-5-carboxylatewere dissolved in 4.5 cm³ of a 0.1 N ethanolic solution of hydrochloricacid containing 1% of water. The solution thereby obtained was stirredfor 3 hours at a temperature in the region of 20° C. and 25 cm³ ofdichloromethane were then added. The organic phase was separated aftersettling has taken place and washed successively two times with 10 cm³of saturated aqueous sodium hydrogen carbonate solution, dried overmagnesium sulfate, filtered and concentrated to dryness under reducedpressure (2.7 kPa) at 40° C. 290 mg of a white foam were obtained, whichwere purified by chromatography on silica gel deposited on plates (gelthickness 1 mm, plates 20×20 cm, eluent: dichloromethane/methanol, 95:5by volume) in 80-mg fractions (4 plates). After localization with UV ofthe zone corresponding to the adsorbed product sought, this zone wasscraped off and the silica collected was washed on sintered glass tentimes with 10 cm³ of ethyl acetate. The filtrates were combined andconcentrated to dryness under reduced pressure (2.7 kPa) at 20° C. Awhite foam was obtained, which was repurified according to the sametechnique (2 plates: 20×20×1 mm; eluent: dichloromethane/methanol, 95:5by volume). 132 mg of4α-acetoxy-2α-benzoyloxy-5β,20-epoxy-1β-hydroxy-7β-methoxy-9-oxo-10β-(3-pyridylcarbonyl)oxy-11-taxen-13α-yl(2R,3S)-3-tert-butoxycarbonylamino-2-hydroxy-3-phenylpropionate werethereby obtained in the form of a white foam, the characteristics ofwhich are as follows:

optical rotation: [α]D₂₀ ^(D)=−34 (c=0.5; methanol).

¹H NMR spectrum (300 MHZ; CDCl₃: chemical shift δ in ppm; couplingconstants J in Hz): 1.30 (s, 3H: —CH₃ at position 16 or 17); 1.35 (s,12H: —C(CH₃)₃ and —CH₃ at position 16 or 170; 1.75 (s, 3H: —CH₃); 1.82and 2.77 (2 mts, 1H each: —CH₂— at position 6); 1.97 (s, 3H: —CH₃); 2.35(d, J=9, 2H: —CH₂— at position 14); 2.39 (s, 3H: —COCH₃); 3.38 (d, J=5,1H: —OH at position 2′); 3.42 (s, 3H: —OCH₃); 3.88 (d, J=7.5, 1H: —H atposition 3); 3.96 (dd, J=11 and 7.5, 1H: —H at position 7); 4.18 and4.32 (2d, J=8.5, 1H each: —CH₂— at position 20); 4.64 (mt, 1H: —H atposition 2′); 4.98 (broad d, J=10, 1H: —H at position 5); 5.28 (broad d,J=10, 1H: —H at position 3′); 5.39 (d, J=10, 1H: —CONH—); 5.70 (d,J=7.5, 1H: —H at position 2); 6.22 (broad t, J=9, 1H: —H at position13); 6.69 (s, 1H: —H at position 10); from 7.25 to 7.45 (mt, 5H: —C₆H₅at position 3′); 7.44 [(dd, J=8.5 and 6, 1H: —OCOC₅H₄N(—H at position5)]; 7.50 [(dd, J=7.5, 2H: —OCOC₆H₅(—H at position 3 and H at position5)]; 7.62 [(t, J=7.5, 1H: —OCOC₆H₅(—H at position 4)]; 8.12 [(d, J=7.5,2H: —OCOC₆H₅(—H at position 2 and —H at position 6)]; 8.35 [(dt, J=8.5and 1, 1H: —OCOC₅H₄N(—H at position 4)]; 8.82 (dd, J=6 and 1, 1H:—OCOC₅H₄N(—H at position 6)]; 9.32 (d, J=1, 1H: —OCOC₅H₄N(—H at position2)].

4α-Acetoxy-2α-benzoyloxy-5β,20-epoxy-1-hydroxy-7β-methoxy-9-oxo-10β-(3-pyridylcarbonyl)oxy-11-taxen-13α-yl(2R,4S,5R)-3-tert-butoxycarbonyl-2-(4-methoxyphenyl)-4-phenyl-1,3-oxazolidine-5-carboxylatewas prepared in the following manner:

290 mg of4α-acetoxy-2α-benzoyloxy-5β,20-epoxy-1β,10β-dihydroxy-7β-methoxy-9-oxo-11-taxen-13α-yl(2R,4S,5R)-3-tert-butoxycarbonyl-2-(4-methoxyphenyl)-4-phenyl-1,3-oxazolidine-5-carboxylate,18.5 mg of 4-(dimethylamino)pyridine, 0.5 g of 4 Å molecular sieve and112 mg of N,N′-dicyclohexylcarbodiimide were added at a temperature inthe region of 20° C. to a solution, kept stirring under an argonatmosphere, of 46 mg of 3-pyridinecarboxylic acid in 25 cm³ of anhydrousethyl acetate. The reaction mixture was kept stirring for 16 hours at atemperature in the region of 20° C., 46 mg of 2-pyridinecarboxylic acid,18.5 mg of 4-(dimethylamino)-pyridine, 0.5 g of 4 Å molecular sieve and112 mg of N,N′-dicyclohexylcarbodiimide were then added and the mixturewas again kept stirring for 24 hours, this cycle then being repeatedtwice more. The reaction mixture was filtered through sintered glasslined with Celite. The sintered glass was washed two times with 50 cm³of ethyl acetate, and the filtrates were combined, washed successivelytwo times with 10 cm² of saturated aqueous sodium hydrogen carbonatesolution and six times with 20 cm³ of distilled water, dried overmagnesium sulfate, filtered and concentrated to dryness under reducedpressure (2.7 kPa) at 40° C. 298 mg of4α-acetoxy-2α-benzoyloxy-5β,20-epoxy-1β-hydroxy-7β-methoxy-9-oxo-10β-(3-pyridylcarbonyl)oxy-11-taxen-13α-yl(2R,4S,5R)-3-tert-butoxycarbonyl-2-(4-methoxyphenyl)-4-phenyl-1,3-oxazolidine-5-carboxylatewere thereby obtained in the form of a white foam.

4α-Acetoxy-2α-benzoyloxy-5β,20-epoxy-1β,10β-dihydroxy-7β-methoxy-9-oxo-11-taxen-13α-yl(2R,4S,5R)-3-tert-butoxycarbonyl-2-(4-methoxyphenyl)-4-phenyl-1,3-oxazolidine-5-carboxylatewas prepared in the following manner:

0.263 cm³ of hydrazine monohydrate were added dropwise and at atemperature in the region of 20° C. to a solution, kept stirring underan argon atmosphere, of 150 mg of4α-acetoxy-2α-benzoyloxy-5β,20-epoxy-1β-hydroxy-7β-methoxy-10β-methoxyacetoxy-9-oxo-11-taxen-13α-yl(2R,4S,5R)-3-tert-butoxycarbonyl-2-(4-methoxyphenyl)-4-phenyl-1,3-oxazolidine-5-carboxylatein 4 cm³ of anhydrous ethanol. The reaction medium was kept stirring for1 hour at a temperature in the region of 20° C. and then poured into amixture of 100 cm³ of ethyl acetate and 50 cm³ of distilled water. Theorganic phase was separated after settling has taken place and theaqueous phase was re-extracted two times with 50 cm³ of ethyl acetate.The organic phases were combined, washed four times with 50 cm³ ofdistilled water, dried over magnesium sulfate, filtered and concentratedto dryness under reduced pressure (2.7 kPa) at 40° C. 180 mg of a whitefoam were obtained, which was purified by chromatography on silica geldeposited on plates [(gel thickness 1 mm, plates 20×20 cm, eluent:dichloromethane/methanol (90:10 by volume)] in 90 mg fractions (2plates). After localization with UV rays of the zone corresponding tothe adsorbed product sought, this zone was scraped off and the silicacollected was washed on sintered glass ten times with 10 cm³ of ethylacetate. The filtrates were combined and concentrated to dryness underreduced pressure (2.7 kPa) at 40° C. 113 mg of4α-acetoxy-2α-benzoyloxy-5β,20-epoxy-1β,10β-dihydroxy-7β-methoxy-9-oxo-11-taxen-13α-yl(2R,4S,5R)-3-tert-butoxycarbonyl-2-(4-methoxyphenyl)-4-phenyl-1,3-oxazolidine-5-carboxylatewere thereby obtained in the form of a white foam.

4α-Acetoxy-2α-benzoyloxy-5β,20-epoxy-1β-hydroxy-7β-methoxy-10β-methoxyacetoxy-9-oxo-11-taxen-13α-yl(2R,4S,5R)-3-tert-butoxycarbonyl-2-(4-methoxyphenyl)-4-phenyl-1,3-oxazolidine-5-carboxylatewas prepared in the following manner:

100 cm³ of an ethanolic suspension of activated nickel prepared byRaney's method (obtained from 80 cm³ of the approximately 50% commercialaqueous suspension, by successive washing fifteen times with 100 cm³ ofdistilled water and four times with 150 cm³ of ethanol to a pH in theregion of 7) were added at a temperature in the region of 20° C. to asolution, kept stirring under an argon atmosphere, of 1.041 g of4α-acetoxy-2α-benzoyloxy-5β,20-epoxy-1β-hydroxy-10β-methoxyacetoxy-7β-methylthiomethoxy-9-oxo-11-taxen-13α-yl(2R,4S,5R)-3-tert-butoxycarbonyl-2-(4-methoxyphenyl)-4-phenyl-1,3-oxazolidine-5-carboxylatein 100 cm³ of anhydrous ethanol. The reaction mixture was kept stirringfor 7 days at a temperature in the region of 20° C. and was thenfiltered through sintered glass. The sintered glass was washed threetimes with 100 cm³ of ethanol and the filtrates were combined andconcentrated to dryness under reduced pressure (2.7 kPa) at 40° C. 821mg of a white foam were obtained, which was purified by chromatographyon 75 g of silica (0.063-0.2 mm) contained in a column 2.5 cm indiameter (eluent: dichloromethane/ethyl acetate, 90:10 by volume),collecting 5-cm³ fractions. The fractions containing only the productsought were pooled and concentrated to dryness under reduced pressure(2.7 kPa) at 40° C. 228 mg of4α-acetoxy-2α-benzoyloxy-5β,20-epoxy-1-hydroxy-7β-methoxy-10β-methoxyacetoxy-9-oxo-11-taxen-13α-yl(2R,4S,5R)-3-tert-butoxycarbonyl-2-(4-methoxyphenyl)-4-phenyl-1,3-oxazolidine-5-carboxylatewere thereby obtained in the form of a white foam.

4α-Acetoxy-2β-benzoyloxy-5β,20-epoxy-1β-hydroxy-10β-methoxyacetoxy-7β-methylthiomethoxy-9-oxo-11-taxen-13α-yl(2R,4S,5R)-3-tert-butoxycarbonyl-2-(4-methoxyphenyl)-4-phenyl-1,3-oxazolidine-5-carboxylatewas prepared in the following manner:

3.35 cm³ of acetic acid and 11.5 cm³ of acetic anhydride were added at atemperature in the region of 20° C. to a solution, kept stirring underan argon atmosphere, of 5 g of4α-acetoxy-2β-benzoyloxy-5β,20-epoxy-1β,7β-dihydroxy-10β-methoxyacetoxy-9-oxo-11-taxen-13α-yl(2R,4S,5R)-3-tert-butoxycarbonyl-2-(4-methoxyphenyl)-4-phenyl-1,3-oxazolidine-5-carboxylatein 165 cm³ of anhydrous dimethyl sulfoxide. The reaction mixture waskept stirring for 3 days at a temperature in the region of 20° C. andwas then poured into 500 cm³ of dichloromethane. 100 cm³ of saturatedaqueous potassium carbonate solution were then added with efficientstirring to a pH in the region of 7. After stirring for 10 minutes, theorganic phase was separated after settling has taken place and theaqueous phase was re-extracted two times with 250 cm³ ofdichloromethane. The organic phases were combined, washed with 3 times100 cm³ of distilled water, dried over magnesium sulfate, filtered andconcentrated to dryness under reduced pressure (2.7 kPa) at 40° C. 9.5 gof a pale yellow oil were obtained, which was purified by chromatographyon 250 g of silica (0.063-0.4 mm) contained in a column 3 cm in diameter[eluent: dichloromethane/methanol (99:1 by volume)], collecting 50 cm³fractions. The fractions containing only the product sought were pooledand concentrated to dryness under reduced pressure (2.7 kPa) at 40° C.3.01 g of4α-acetoxy-2β-benzoyloxy-5β,20-epoxy-1-hydroxy-10β-methoxyacetoxy-7β-methylthiomethoxy-9-oxo-11-taxen-13α-yl(2R,4S,5R)-3-tert-butoxycarbonyl-2-(4-methoxyphenyl)-4-phenyl-1,3-oxazolidine-5-carboxylatewere thereby obtained in the form of a white foam.

4α-Acetoxy-2β-benzoyloxy-5β,20-epoxy-1β,7β-dihydroxy-10β-methoxyacetoxy-9-oxo-11-taxen-13α-yl(2R,4S,5R)-3-tert-butoxycarbonyl-2-(4-methoxyphenyl)-4-phenyl-1,3-oxazolidine-5-carboxylatewas prepared in the following manner:

220 cm³ of triethylamine/hydrofluoric acid (mole ratio 1:3) complex wereadded dropwise at a temperature in the region of 0° C. to a solution,kept stirring under an argon atmosphere, of 20 g of4α-acetoxy-2α-benzoyloxy-5β,20-epoxy-7β-triethylsilyloxy-1β-hydroxy-10β-methoxyacetoxy-9-oxo-11-taxen-13α-yl(2R,4S,5R)-3-tert-butoxycarbonyl-2-(4-methoxyphenyl)-4-phenyl-1,3-oxazolidine-5-carboxylatein 200 cm³ of anhydrous dichloromethane. The reaction mixture was thenwarmed to a temperature in the region of 20° C., maintained for 3 hoursat this temperature and poured into 4 liters of saturated aqueous sodiumhydrogen carbonate solution. The pH of the reaction medium thus beingbrought to around 7. After stirring for 10 minutes, the organic phasewas separated after settling has taken place and the aqueous phase wasextracted two times with 100 cm³ of dichloromethane. The organic phaseswere combined, washed with 100 cm³ of distilled water, dried overmagnesium sulfate, filtered and concentrated to dryness under reducedpressure (2.7 kPa) at 40° C. 17.4 g of4α-acetoxy-2α-benzoyloxy-5β,20-epoxy-1β,7β-dihydroxy-10β-methoxyacetoxy-9-oxo-11-taxen-13α-yl(2R,4S,5R)-3-tert-butoxycarbonyl-2-(4-methoxyphenyl)-4-phenyl-1,3-oxazolidine-5-carboxylatewere thereby obtained in the form of a white foam.

4α-Acetoxy-2α-benzoyloxy-5β,20-epoxy-7β-triethylsilyloxy-1β-hydroxy-10β-methoxyacetoxy-9-oxo-11-taxen-13α-yl(2R,4S,5R)-3-tert-butoxycarbonyl-2-(4-methoxyphenyl)-4-phenyl-1,3-oxazolidine-5-carboxylatewas prepared under the conditions described in International ApplicationPCT WO 95/11241.

EXAMPLE 2

Working as in Example 1, but starting from 210 mg of4α-acetoxy-2α-benzoyloxy-5β,20-epoxy-1β-hydroxy-7β-methoxy-9-oxo-10β-(2-pyridylcarbonyl)oxy-11-taxen-13α-yl(2R,4S,5R)-3-tert-butoxycarbonyl-2-(4-methoxyphenyl)-4-phenyl-1,3-oxazolidine-5-carboxylate,145 mg of4α-acetoxy-2α-benzoyloxy-5β,20-epoxy-1β-hydroxy-7β-methoxy-9-oxo-10β-(2-pyridylcarbonyl)oxy-11-taxen-13α-yl(2R,3S)-3-tert-butoxycarbonylamino-2-hydroxy-3-phenylpropionate wereobtained in the form of a white foam, the characteristics of which areas follows:

optical rotation: [α]D₂₀ ^(D)=−52 (c=0.5; methanol).

¹H NMR spectrum (400 MHZ: CDCl₃); chemical shifts δ in pp,; couplingconstants J in Hz): 1.31 (s, 3H: —CH₃ at position 16 or 17); 1.37 [(s,12H: —C(CH₃)₃ and —CH₃ at position 16 or 171; 1.74 (s, 1H: —OH atposition 1); 1.78 (s, 3H: —CH₃); 1.82 and 2.78 (2 mts, 1H each: —CH₂— atposition 6); 1.97 (s, 3H: —CH₃); 2.35 (d, J=9, 2H: —CH₂— at position14); 2.40 (s, 3H: —COCH₃); 3.40 (d, J=4.5, 1H: —OH at position 2′); 3.43(s, 3H: —OCH₃); 3.92 (d, J=7.5, 1H: —H at position 3); 3.98 (dd, J=11and 7, 1H: —H at position 7); 4.20 and 4.32 (2 d, J=8.5, 1H each: —CH₂—at position 20); 4.64 (mt, 1H: —H at position 2′); 5.00 (broad d, J=10,1H: —H at position 5); 5.28 (broad d, J=10, 1H: —H at position 3′); 5.43(d, J=10, 1H: —CONH—); 5.73 (d, J=7.5, 1H: —H at position 2); 6.22(broad t, J=9, 1H: —H at 13); 6.67 (s, 1H: —H at position 10); from 7.25to 7.45 (mt, 5H: —C₆H₅ at position 3′); 7.51 [(mt, 3H: —OCOC₆H₅ (—H atposition 3 and H at position 5) and —OCOC₅H₄N(—H at position 5)]; 7.61[(t, J =7.5, 1H: —OCOC₆H₅(—H at position 4)]; 7.88 [(split t, J =8 and1, 1H: —OCOC₅H₄N(—H at position 4)]; 8.12 [(d, J=7.5, 2H: —OCOC₆H₅(—H atposition 2 and —H at position 6)]; 8.20 (broad d, J=8, 1H: —OCOC₅H₄N(—Hat position 3)]; 8.82 (broad dd J=5 and 1, 1H: —OCOC₅H₄N(—H at position6)].

Working as in Example 1, but starting from 300 mg of4α-acetoxy-2α-benzoyloxy-5β,20-epoxy-1β,10β-dihydroxy-7β-methoxy-9-oxo-11-taxen-13α-yl(2R,4S,5R)-3-tert-butoxycarbonyl-2-(4-methoxyphenyl)-4-phenyl-1,3-oxazolidine-5-carboxylate,230 mg of4α-acetoxy-2α-benzoyloxy-5β,20-epoxy-1β-hydroxy-7β-methoxy-9-oxo-10β-(2-pyridylcarbonyl)oxy-11-taxen-13α-yl(2R,4S,5R)-3-tert-butoxycarbonyl-2-(4-methoxyphenyl)-4-phenyl-1,3-oxazolidine-5-carboxylatewere obtained in the form of a white foam.

EXAMPLE 3

Working as in Example 1, but starting from 300 mg of4α-acetoxy-2α-benzoyloxy-10β-cyclopentylcarbonyloxy-5β,20-epoxy-1β-hydroxy-7β-methoxy-9-oxo-11-taxen-13α-yl(2R,4S,5R)-3-tert-butoxycarbonyl-2-(4-methoxyphenyl)-4-phenyl-1,3-oxazolidine-5-carboxylate,96 mg of4α-acetoxy-2α-benzoyloxy-10β-cyclopentylcarbonyloxy-5β,20-epoxy-11β-hydroxy-7β-methoxy-9-oxo-11-taxen-13α-yl(2R,3S)-3-tert-butoxycarbonylamino-2-hydroxy-3-phenylpropionate wereobtained in the form of a white foam, the characteristics of which areas follows:

optical rotation: [α]₂₀ ^(D)=−66 (c=0.5; methanol).

¹H NMR spectrum (400 MHZ; CDCl₃; chemical shifts δ in ppm; couplingconstants J in Hz); 1.25 (s, 6H: —CH ₃ at positions 16 and 17); 1.39 [s,9H; —C(CH ₃)₃]; from 1.55 to 1.80 and from 1.90 to 2.10 (2 mts, 4H each:—CH ₂— of the cyclopentyl); 1.71 (s, 1H: —OH at position 1); 1.75 (s,3H: —CH ₃); 1.82 and 2.75 (2 mts, 1H each: —CH ₂— at position 6); 1.93(s, 3H: —CH ₃); 2.33 (d, J=9 Hz, 2H: —CH ₂— at position 14); 2.39 (s,3H: —COCH ₃); 2.95 (mt, 1H: ═CH— of the cyclopentyl); 3.38 (s, 3H: —OCH₃); 3.40 (d, J =5, 1H: —OH at position 2′); 3.88 (d, J=7.5, 1H: —H atposition 3); 3.91 (dd, J=11 and 7.5, 1H: —H at position 7); 4.19 and4.32 (2 d, J=8.5, 1H each: —CH ₂ at position 20); 4.65 (mt, 1H: —H atposition 2′); 4.98 (broad d, J=10, 1H: —H at position 5); 5.28 (broad d,J=10, 1H: —H at position 3′); 5.41 (d, J=10, 1H: —CONH—); 5.68 (d, J=7.5, 1H: —H at position 2); 6.21 (broad t, J=9, 1H: —H at position 13);6.45 (s, 1H: —H at position 10); from 7.25 to 7.45 (mt, 5H: —C₆ H ₅ atposition 3′); 7.51 [t, J=7.5, 2H: —OCOC₆H₅ (—H at position 3 and H atposition 5); 7.63 (t, J=7.5, 1H: —OCOC₆H₅ (—H at position 4)); 8.12 (d,J=7.5, 2H: —OCOC₆H₅ (—H at position 2 and —H at position 6)).

Working as in Example 1, but starting from 300 mg of4α-acetoxy-2α-benzoyloxy-5β,20-epoxy-1β,10β-dihydroxy-7β-methoxy-9-oxo-11-taxen-13α-yl(2R,4S,5R)-3-tert-butoxycarbonyl-2-(4-methoxyphenyl)-4-phenyl-1,3-oxazolidine-5-carboxylate,410 mg of4α-acetoxy-2α-benzoyloxy-10β-cyclopentylcarbonyloxy-5β,20-epoxy-1β-hydroxy-7β-methoxy-9-oxo-11-taxen-13α-yl(2R,4S,5R)-3-tert-butoxycarbonyl-2-(4-methoxyphenyl)-4-phenyl-1,3-oxazolidine-5-carboxylatewere obtained in the form of a white foam.

EXAMPLE 4

Working as in Example 1, but starting from 300 mg of4α-acetoxy-2α-benzoyloxy-10β-cyclopropylcarbonyloxy-5β,20-epoxy-1β-hydroxy-7β-methoxy-9-oxo-11-taxen-13α-yl(2R,4S,5R)-3-tert-butoxycarbonyl-2-(4-methoxyphenyl)-4-phenyl-1,3-oxazolidine-5-carboxylate,130 mg of4α-acetoxy-2α-benzoyloxy-10β-cyclopropylcarbonyloxy-5β,20-epoxy-1β-hydroxy-7β-methoxy-9-oxo-11-taxen-13α-yl(2R,3S)-3-tert-butoxycarbonylamino-2-hydroxy-3-phenylpropionate wereobtained in the form of a white foam, the characteristics of which areas follows:

optical rotation: [α]₂₀ ^(D)=−71 (c=0.5; methanol).

¹H NMR spectrum (400 MHZ; CDCl₃, chemical shifts δ in ppm; couplingconstants J in Hz): 1.00 and 1.19 (2 mts, 2H each: —CH ₂— of thecyclopropyl); 1.25 (s, 3H: —CH ₃ at position 16 or 17); 1.27 (s, 3H: —CH₃ at position 16 or 17); 1.39 [s, 9H: —C(CH ₃)₃]; 1.71 (s, 1H: —OH atposition 1); 1.75 (s, 3H: —CH ₃); from 1.70 to 1.90 (mt, 1H: ═CH— of thecyclopropyl); 1.82 and 2.75 (2 mts, 1H each: —CH ₂— at position 6); 1.93(s, 3H: —CH ₃); 2.33 (d, J=9, 2H: —CH ₂— at position 14); 2.40 (s, 3H:—COCH ₃); 3.35 (s, 3H: —OCH ₃); 3.40 (d, J=5, 1H: —OH at position 2′);3.88 (d, J=7.5, 1H: —H at position 3); 3.89 (dd, J=11 and 7.5, 1H: —H atposition 7); 4.19 and 4.32 (2 d, J=8.5, 1H each: —CH ₂— at position 20);4.65 (mt, 1H: —H at position 2′); 5.00 (broad d, J=10, 1H: —H atposition 5); 5.28 (broad d, J=10, 1H: —H at position 3′); 5.42 (d, J=10,1H: —CONH—); 5.68 (d, J=7.5, 1H: —H at position 2); 6.21 (broad t, J=9,1H: —H at position 13); 6.48 (s, 1H: —H at position 10); from 7.25 to7.45 (mt, 5H: —C₆ H ₅ at position 3′); 7.52 (t, J=7.5, 2H: —OCOC₆H₅ (—Hat position 3 and H at position 5)); 7.64 (t, J=7.5, 1H: —OCOC₆H₅ (—H atposition 4)); 8.12 (d, J=7.5, 2H: —OCOC₆H₅ (—H at position 2 and —H atposition 6)).

Working as in Example 1, but starting from 300 mg of4α-acetoxy-2α-benzoyloxy-5β,20-epoxy-1β,10β-dihydroxy-7β-methoxy-9-oxo-11-taxen-13α-yl(2R,4S,5R)-3-tert-butoxycarbonyl-2-(4-methoxyphenyl)-4-phenyl-1,3-oxazolidine-5-carboxylate,435 mg of4α-acetoxy-2α-benzoyloxy-10β-cyclopropylcarbonyloxy-5β,20-epoxy-1β-hydroxy-7β-methoxy-9-oxo-11-taxen-13α-yl(2R,4S,5R)-3-tert-butoxycarbonyl-2-(4-methoxyphenyl)-4-phenyl-1,3-oxazolidine-5-carboxylatewere obtained in the form of a white foam.

EXAMPLE 5

Working as in Example 1, but starting from 430 mg of4α-acetoxy-2α-benzoyloxy-5β,20-epoxy-1β-hydroxy-7β-methoxy-10β-methoxyacetoxy-9-oxo-11-taxen-13α-yl(2R,4S,5R)-3-tert-butoxycarbonyl-2-(4-methoxyphenyl)-4-phenyl-1,3-oxazolidine-5-carboxylate,164 mg of4α-acetoxy-2α-benzoyloxy-5β,20-epoxy-1β-hydroxy-7β-methoxy-10β-methoxyacetoxy-9-oxo-11-taxen-13α-yl(2R,3S)-3-tert-butoxycarbonylamino-2-hydroxy-3-phenylpropionate wereobtained in the form of a white foam, the characteristics of which areas follows:

optical rotation: [α]₂₀ ^(D)=−48 (c=0.5; methanol)

¹H NMR spectrum (300 MHZ: CDCl₃; δ in ppm; coupling constants J in Hz):1.17 (s, 3H: —H ₃); 1.22 (s, 3H: —CH ₃); 1.35 (s, 9H: —C(CH ₃)₃; 1.75(s, 3H: —CH ₃); 1.80 and 2.75 (2 mts, 1 H each: —CH ₂— 6); 1.90 (s, 3H:—CH ₃); 2.30 (d, J=9, 2H: —CH ₂— 14); 2.37 (s, 3H: —COCH ₃); 3.35 and3.55 (2 s, 3H each: —OCH ₃); 3.40 (d, J=5, 1H: —OH 2′); 3.85 (d, J=7,1H: —H 3); 3.88 (dd, J=11 and 7, 1H: —H 7); 4.17 and 4.32 (2 d, J=8.5,1H each: —CH ₂— 20); 4.19 and 4.27 (2 d, J=15, 1H each: —OCOCH ₂OCH₃);4.65 (mt, 1H: —H 2′); 4.97 (broad d, J=10, 1H: —H 5); 5.25 (broad d,J=10, 1H: —H 3′); 5.42 (d, J=10, 1H: —CONH—); 5.66 (d, J=7, 1H: —H 2);6.18 (broad t, J=9, 1H: —H 13); 6.52 (s, 1H: —H 10); from 7.30 to 7.50(mt, 5H: —C₆ H ₅ 3′); 7.51 ((t, J =7.5, 2H: —OCOC₆H₅(—H 3 and H 5));7.63 ((t, J=7.5, 1H: —OCOC₆H₅(—H 4)); 8.12 (d, J=7.5, 2H: —OCOC₆H₅(—H 2and H 6)).

EXAMPLE 6

Working as in example 1, but starting from4α-acetoxy-2β-benzoyloxy-5β,20epoxy-1β-hydroxy-10β-methoxyacetoxy-7β-methylthiomethoxy-9-oxo-11-taxen-13α-yl(2R,4S,SR)-3-tert-butoxycarbonyl-2-(4-methoxyphenyl)-4-phenyl-1,3-oxazolidine-5-carboxylate,98 mg of4α-acetoxy-2α-benzoyloxy-5β,20-epoxy-1β-hydroxy-7β-methylthiomethoxy-9-oxo-10β-methoxyacetoxy-11-taxen-13α-yl(2R,3S)-3-tert-butoxycarbonylamino-2-hydroxy-3-phenyl propionate of thefollowing structure was obtained:

NMR spectrum: ¹H (400 MHZ, CDCl₃, δ ppm): 1.25 (s: 6H); 1.38 (s: 9H);1.71 (s: 1H); 1.78 (s: 3H); 1.88 (mt: 1H); 2.03 (s: 3H); 2.16 (s: 3H);2.34 (d, J=9 Hz: 2H); 2.42 (s: 3H); 2.85 (mt: 1H); 3.38 (d, J=5 Hz: 1H);3.53 (s: 3H); 3.89 (d, J=7.5 Hz: 1H); 4.15 (d, J=16 Hz: 1H); 4.20 (d,J=8.5 Hz: 1H); 4.27 (d, J=16 Hz: 1H); from 4.30 to 4.40 (mt: 1H); 4.32(d, J=8.5 Hz: 1H); 4.65 (mt: 1H); 4.71 (AB pattern, J=12 Hz: 2H); 4.98(d large, J =10 Hz: 1H); 5.28 (d large, J=10 Hz: 1H); 5.40 (d, J=10 Hz:1H); 5.72 (d, J=7.5 Hz: 1H); 6.22 (t large, J=9 Hz: 1H); 6.67 (s: 1H);from 7.25 to 7.45 (mt: 5H); 7.52 (t, J=7.5 Hz: 2H); 7.64 (t, J=7.5 Hz:1H); 8.12 (d, J=7.5Hz: 2H).

EXAMPLE 7

The intermediate

when treated with HCl/EtOH by the method of Example 1 can generate4α-acetoxy-2α-benzoyloxy-5β,20-epoxy-1βhydroxy-7β-methylthiomethoxy-9-oxo-10β-acetyl-11-taxen-13α-yl(2R,3S)-3-tert-butoxycarbonylamino-2-hydroxy-3-phenyl propionate.

EXAMPLE 8 Process for Preparing 7-Alkylthioalkoxy Derivatives: Couplingof Taxenes with Phenyloxazolidine Carboxylic Acids

A solution of 52 g of4,10β-diacetoxy-2α-benzoyloxy-5β20-epoxyl,13α-dihydroxy-7β-triethylsiloxy-9-oxo-tax-11-ene(SIBAC (XXX))

in 850 ml ethyl acetate was dehydrated by distillation under 70 mmHg ofpressure until a volume of 360 ml of distillate was obtained. Theresulting solution was chilled to 0° C. 44.6 g(2R,4S,5R)-3-benzoyl-2-(4-methoxyphenyl)-4-phenyloxazolidine-5-carboxylicacid (XXXa)

was added to this solution, followed by rinsing with 20 ml ethylacetate. 22.4 g dicyclohexylcarbodiimide and 1.77 g4-dimethylamino-pyridine were then successively added to the solution,followed by an additional rinse with 30 ml ethyl acetate. The reactionmedium was maintained for about 4 hours at 5° C., whereupon the DCU(dicyclohexylurea) that was formed was filtered off. After the DCU waswashed three times (each time with 270 ml ethyl acetate), the washingorganic phases and the filtrate were recombined and washed twice at roomtemperature, each time with 815 ml of a 5% sodium bicarbonate solution.The organic phase was then dried with 136 g of MgSO₄ and evaporated todryness at 35° C. under reduced pressure. The extract was taken up with200 ml of methanol and then evaporated again to dryness. The dry extractwas crystallized at about 30° C. in about 350 ml of methanol. Theresulting suspension was chilled to 0° C. over a period of two hours andthen kept at this temperature for 30 minutes. The product was thenfiltered, washed three times (each time with 40 ml frozen methanol), andthen dried under 5 mmHg of pressure at room temperature. 75.5 g of thecoupled ester (XXXI),

(2R,4S,5R)-3-benzoyl-2-(4-methoxyphenyl)-4-phenyloxazolidine-5-carboxylateof 4,10β-diacetoxy-2α-benzoyloxy-5β,20-epoxy-1,13α-dihydroxy-7β-triethylsiloxy-9-oxo-tax-11-ene wereobtained.

Preparation of the Desilylated Product (XXXII)

Starting with a solution of 72 g of(2R,4S,5R)-3-benzoyl-2-(4-methoxyphenyl)-4-phenyloxazolidine-5-carboxylateof4,10β-diacetoxy-2α-benzoyloxy-5β,20-epoxy-1,13α-dihydroxy-7β-triethylsiloxy-9-oxo-tax-11-enein 360 ml methylene chloride, 74.8 g of 3HF.TEA (hydrofluoricacid.triethylamine) was added over 15 minutes and at room temperature.This was then left under agitation for approximately 16.5 hours. Afterthe addition of 5.4 ml of 3HF.TEA and three hours of additionalagitation to complete the reaction, the reaction mixture was washed with300 ml of water and the aqueous phase was counter-extracted with 325 mlmethylene chloride. The organic phases were recombined, and then washed,in succession, with 360 ml water, with a solution of 15 g sodiumbicarbonate in 360 ml water, and then with 360 ml water. The organicphase was then concentrated to dryness under reduced pressure at 40° C.,whereupon the product was left to dry at 30° C. under 5 mmHg ofpressure. Yield: 66.6 g of(2R,4S,5R)-3-benzoyl-2-(4-methoxyphenyl)-4-phenyloxazolidine-5-carboxylateof4,10β-diacetoxy-2α-benzoyloxy-5β,20-epoxy-1,7β,13α-trihydroxy-9-oxo-tax-11-ene.

Preparation of the Methylthiomethylether Derivative (XXXIII)

Starting with a solution of 60 g of(2R,4S,5R)-3-benzoyl-2-(4-methoxyphenyl)-4-phenyloxazolidine-5-carboxylateof4,10β-diacetoxy-2α-benzoyloxy-5β,20-epoxy-1,7β,13α-trihydroxy-9-oxo-tax-11-enein 1,500 ml of DMSO (pre-dried on a molecular sieve), 1,200 ml of aceticacid was poured, over a period of 30 minutes, followed by 321 ml aceticanhydride over a period of 10 minutes. The reaction mixture was thenleft under agitation for about 21 hours at room temperature. Followingthe addition of 3,600 ml of ethyl acetate, the organic phase was washedwith 2,335 g of sodium bicarbonate in 28 liters of water (800 ml ofethyl acetate are added during the operations), then again twice, eachtime with 1,800 ml water, and then washed once more with 900 ml water.The organic phase was then concentrated to dryness under reducedpressure at 40° C. Yield: 84 g of(2R,4S,5R)-3-benzoyl-2-(4-methoxyphenyl)-4-phenyloxazolidine-5-carboxylateof4,10β-diacetoxy-2α-benzoyloxy-5β,20-epoxy-1,13α-dihydroxy-7β-methylthiomethyloxy-9-oxo-tax-11-ene

in oil form. The product was taken up in 154 g of ethyl acetate forfurther manipulation.

Obtaining the Final Product (XXXIV)

80 g of ethyl acetate and 4.5 ml of HCl were added to 230 g of thepreceding solution. After agitation at room temperature for 30 minutes,the organic phase was washed four times, each time with 140 ml of a 17%sodium chloride aqueous solution, then dried with 50 g of MgSO₄ andconcentrated to dryness under reduced pressure at 35° C. 70.8 g of rawproduct were obtained and were dissolved in 70 g ethyl acetate. Theproduct was purified by chromatography on silica gel using ethylacetate/cyclohexane (45/55 v/v). Thus, from 92 g of solution, 30 g ofpure (2R,3S)-3-benzoyl-2-hydroxy-3-phenyl propionate of4,10β-diacetoxy-2α-benzoyloxy-5β,20-epoxy-1,13α-dihydroxy-7β-methylthiomethyloxy-9-oxo-tax-11-ene

were obtained after concentration of the fractions to dryness andfurther drying of the dry extract under a pressure of 5 mmHg at roomtemperature.

The new products of general formula (I) in which Z represents a radicalof general formula (II) manifest significant inhibitory activity withrespect to abnormal cell proliferation, and possess therapeuticproperties permitting the treatment of patients having pathologicalconditions associated with abnormal cell proliferation. The pathologicalconditions include the abnormal cell proliferation of malignant ornon-malignant cells of various tissues and/or organs, comprising,without implied limitation, muscle, bone or connective tissue, the skin,brain, lungs, sex organs, the lymphatic or renal systems, mammary orblood cells, liver, the digestive system, pancreas and thyroid oradrenal glands. These pathological conditions can also includepsoriasis, solid tumors, cancers of the ovary, breast, brain, prostate,colon, stomach, kidney or testicles, Kaposi's sarcoma,cholangiocarcinoma, choriocarcinoma, neuroblastoma, Wilms' tumor,Hodgkin's disease, melanoma, multiple myeloma, chronic lymphocyticleukemia and acute or chronic granulocytic lymphoma. The new productsaccording to the invention are especially useful for the treatment ofcancer of the ovary. The products according to the invention may be usedto prevent or delay the appearance or reappearance of the pathologicalconditions, or to treat these pathological conditions.

The products according to the invention may be administered to a patientaccording to different dosage forms suited to the chosen administrationroute, which was preferably the parenteral route. Parenteraladministration comprises intravenous, intraperitoneal, intramuscular orsubcutaneous administration. Intraperitoneal or intravenousadministration was more especially preferred.

The present invention also comprises preparing pharmaceuticalcompositions containing at least one product of general formula (I), ina sufficient amount suitable for use in human or veterinary therapy. Thepreparations of these compositions may be accomplished according to thecustomary methods, using one or more pharmaceutically acceptableadjuvants, vehicles or excipients. Suitable vehicles include diluents,sterile aqueous media and various non-toxic solvents. Preferably, thecompositions take the form of aqueous solutions or suspensions,injectable solutions which can contain emulsifying agents, colorings,preservatives or stabilizers. However, the compositions can also takethe form of tablets, pills, powders or granules which can beadministered orally.

The choice of adjuvants or excipients may be determined by thesolubility and the chemical properties of the product, the particularmode of administration and good pharmaceutical practice.

For parenteral administration, sterile, aqueous or non-aqueous solutionsor suspensions are used. For the preparation of non-aqueous solutions orsuspensions, natural vegetable oils such as olive oil, sesame oil orliquid petroleum, or injectable organic esters such as ethyl oleate, maybe used. The sterile aqueous solutions can consist of a solution of apharmaceutically acceptable salt dissolved in water. The aqueoussolutions are suitable for intravenous administration provided the pH isappropriately adjusted and the solution is made isotonic, for examplewith a sufficient amount of sodium chloride or glucose. Thesterilization may be carried out by heating or by any other means whichdoes not adversely affect the composition.

It is clearly understood that all the products participating in thecompositions according to the invention must be pure and non-toxic inthe amounts used.

The compositions can contain at least 0.01% of therapeutically activeproduct. The amount of active product in a composition is such that asuitable dosage can be prescribed. Preferably, the compositions areprepared in such a way that a single dose contains from 0.01 to 1000 mgapproximately of active product for parenteral administration.

The therapeutic treatment may be performed concurrently with othertherapeutic treatments including anti-neoplastic drugs, monoclonalantibodies, immunotherapy or radiotherapy or biological responsemodifiers. The response modifiers include, without implied limitation,lymphokines and cytokines such as interleukins, interferons (α, β or δ)and TNF. Other chemotherapeutic agents which are useful in the treatmentof disorders due to abnormal cell proliferation include, without impliedlimitation, alkylating agents, for instance nitrogen mustards such asmechloretamine, cyclophosphamide, melphalan and chlorambucil, alkylsulfonates such as busulfan, nitrosoureas such as carmustine, lomustine,semustine and streptozocin, triazenes such as dacarbazine,antimetabolites such as folic acid analogues, for instance methotrexate,pyrimidine analogues such as fluorouracil and cytarabine, purineanalogues such as mercaptopurine and thioguanine, natural products, forinstance Vinca alkaloids such as vinblastine, vincristine and vindesine,epipodophyllotoxins such as etoposide and teniposide, antibiotics suchas dactinomycin, daunorubicin, doxorubicin, bleomycin, plicamycin andmitomycin, enzymes such as L-asparaginase, various agents such ascoordination complexes of platinum, for instance cisplatin, substitutedureas such as hydroxyurea, methylhydrazine derivatives such asprocarbazine, adrenocortical suppressants such as mitotane andaminoglutethimide, hormones and antagonists such asadrenocorticosteroids such as prednisone, progestins such ashydroxyprogesterone caproate, methoxyprogesterone acetate and megestrolacetate, oestrogens such as diethylstilboestrol and ethynyloestradiol,anti-estrogens such as tamoxifen, and androgens such as testosteronepropionate and fluoxymesterone.

The doses used for carrying out the methods according to the inventionare those which permit a prophylactic treatment or a maximum therapeuticresponse. The doses vary according to the administration form, theparticular product selected and features distinctive to the subject tobe treated. In general, the doses are those which are therapeuticallyeffective for the treatment of disorders due to abnormal cellproliferation. The products according to the invention may beadministered as often as necessary to obtain the desired therapeuticeffect. Some patients may respond rapidly to relatively high or lowdoses, and then require low or zero maintenance doses. Generally, lowdoses will be used at the beginning of the treatment and, if necessary,increasingly stronger doses will be administered until an optimum effectis obtained. For other patients, it may be necessary to administermaintenance doses 1 to 8 times a day, and preferably 1 to 4 times,according to the physiological requirements of the patient in question.It is also possible that some patients may require the use of only oneto two daily administrations.

In man, the doses are generally between 0.01 and 200 mg/kg. Forintraperitoneal administration, the doses will generally be between 0.1and 100 mg/kg, preferably between 0.5 and 50 mg/kg and still morespecifically between 1 and 10 mg/kg. For intravenous administration, thedoses are generally between 0.1 and 50 mg/kg, preferably between 0.1 and5 mg/kg and still more specifically between 1 and 2 mg/kg. It isunderstood that, in order to choose the most suitable dosage, accountshould be taken of the administration route, the patient's weight,general state of health and age and all factors which may influence theefficacy of the treatment.

The example which follows illustrates a composition according to theinvention.

PHARMACOLOGICAL EXAMPLE

40 mg of the product obtained in Example 1 are dissolved in 1 cm³ ofEMULPHOR® EL 620 (Stepan Canada, Inc.) and 1 cm³ of ethanol, and thesolution is then diluted by adding 18 cm³ of physiological saline.

The composition is administered by perfusion over 1 hour by introductionin physiological solution.

The present invention may be embodied in other specific forms withoutdeparting from its spirit or essential characteristics. The describedembodiments are to be considered in all respects as illustrative onlyand not restrictive.

The scope of the invention is, therefore, indicated by the appendedclaims rather than by the foregoing description. All changes which comewithin the meaning and range of equivalency of the claims are to beembraced within their scope.

We claim:
 1. A method of preparing a taxoid of general formula:

in which: Z represents a hydrogen atom or a radical of general formula:

in which: R₁ represents a benzoyl radical unsubstituted or substitutedwith one or more identical or different atoms or radicals selected fromhalogen atoms, and alkyl radicals containing 1 to 4 carbon atoms, alkoxyradicals containing 1 to 4 carbon atoms or trifluoromethyl radicals, athenoyl radical, a furoyl radical, and a radical R₂—O—C(═O)—, in whichR₂ represents an alkyl radical containing 1 to 8 carbon atoms, analkenyl radical containing 2 to 8 carbon atoms, an alkynyl radicalcontaining 3 to 8 carbon atoms, a cycloalkyl radical containing 3 to 6carbon atoms, a cycloalkenyl radical containing 4 to 6 carbon atoms, aphenyl atoms, alkyl radicals containing 1 to 4 carbon atoms, and alkoxyradicals containing 1 to 4 carbon atoms), cyano radicals, carboxylradicals, and alkoxycarbonyl radicals in which the alkyl portioncontains 1 to 4 carbon atoms; R₃ represents a phenyl radical; R₄represents an alkanoyloxy radical in which the alkanoyl portion contains2 to 6 carbon atoms in an unbranched or branched chain; and R₅represents an alkoxy radical containing 1 to 4 carbon atoms in anunbranched or branched chain, substituted by an alkylthio radicalcontaining 1 to 4 carbon atoms, comprising: silylating a baccatin offormula (IX)

to obtain a silylated baccatin, where the silylation occurs at position7; acetylating said silylated baccatin to obtain a protected baccatin,wherein said acetylation occurs at position 10; coupling the protectedbaccatin with an oxazolidine ring optionally monosubstituted orgem-disubstituted at position 2 to produce a coupled ester; deprotectingsaid coupled ester with an acid to produce a desilylated taxoid;reacting said desilylated taxoid in a Pummerer reaction to produce amethylthiomethylether derivative; and deprotecting saidmethylthiomethylether derivative with an acid to produce the desiredtaxoid.
 2. The method for preparing a taxoid according to claim 1 inwhich Z represents a radical of general formula (II), in which R₁represents a benzoyl radical or a radical R₂—O—C(═O)— in which R₂represents a tert-butyl radical; R₃ represents a phenyl radical; R₄represents an alkanoyloxy radical in which the alkanoyl portion contains2 to 4 carbon atoms; and R₅ represents an alkoxy radical containing 1 to4 carbon atoms substituted by a methylthio radical.
 3. The method forpreparing a taxoid according to claim 1 for which Z represents ahydrogen atom or a radical of general formula (II) in which R₁represents a benzoyl radical or a radical R₂—O—C(═O)— in which R₂represents a tert-butyl radical; R₃ represents a phenyl radical; R₄represents an acetoxy or methoxyacetoxy radical; and R₅ represents amethylthiomethoxy radical.
 4. The method of preparing a taxoid of claim1, wherein R₄ is acetoxy.
 5. The method of claim 1 wherein the taxoid(2R,3S)-3-benzoyl-2-hydroxy-3-phenyl propionate of4,10β-diacetoxy-2α-benzoyloxy-5β,20-epoxy-1,13α-dihydroxy-7β-methylthiomethyloxy-9-oxo-tax-11-ene(XXXIV)

is prepared.
 6. The method of claim 1 wherein the taxoid (2R,4S,5R)-3-benzoyl-2-(4-methoxyphenyl)-4-phenyloxazolidine-5-carboxylate of4,10β-diacetoxy-2α-benzoyloxy-5β,20-epoxy-1,13α-dihydroxy-7β-methylthiomethyloxy-9-oxo-tax-11-ene(XXXIII)

is prepared.
 7. A method of preparing a pharmaceutical composition,comprising preparing least one taxoid by the method of claim 1, in whichZ represents a radical of general formula (II), and combining said atleast one taxoid with one or more pharmaceutically acceptable carriers.8. A method of preparing a pharmaceutical composition, comprisingpreparing at least one taxoid by the method of claim 5 or claim 6, andcombining said at least one taxoid with one or more pharmaceuticallyacceptable carriers.
 9. The method of claim 8, wherein thepharmaceutically acceptable carrier is a diluent or adjuvant.
 10. Themethod of claim 8, further comprising another pharmacologically activecompound.
 11. The method of claim 9, further comprising anotherpharmacologically active compound.
 12. A method of preparing a taxoid ofgeneral formula (XIV)

comprising: silylating the baccatin of formula (IX)

to obtain a silylated baccatin wherein said silylation occurs atposition 7; acetylating said silylated baccatin to obtain a protectedbaccatin of formula (XXX), wherein said acetylation occurs at position10; coupling the protected baccatin of formula (XXX)

with a compound of formula (XXXa)

to produce a coupled ester of formula (XXXI);

deprotecting said coupled ester with an acid to produce a desilylatedtaxoid of formula (XXXII);

reacting said desilylated taxoid in a Pummerer reaction to produce amethylthiomethylether derivative of formula (XXXIII);

and deprotecting said methylthiomethylether derivative with an acid toproduce a compound of formula (XXXIV).